Golang基于Redis bitmap实现布隆过滤器（完结版）

package main
 
import (
    "fmt"
    "github.com/go-redis/redis/v8"
    "github.com/willf/bitset"
)
 
// 定义布隆过滤器结构体
type BloomFilter struct {
    redisClient *redis.Client // Redis客户端
    keyPrefix   string        // Redis键的前缀
    bitSets     []*bitset.BitSet
    bitSetCount int // 位集数量
    hashCount   int // 哈希函数数量
}
 
// 初始化布隆过滤器
func NewBloomFilter(redisClient *redis.Client, keyPrefix string, size, hashCount int) *BloomFilter {
    return &BloomFilter{
        redisClient: redisClient,
        keyPrefix:   keyPrefix,
        bitSetCount: size,
        hashCount:   hashCount,
    }
}
 
// 添加元素到布隆过滤器
func (bf *BloomFilter) Add(key string) error {
    for i := 0; i < bf.bitSetCount; i++ {
        bitSetKey := fmt.Sprintf("%s:%d", bf.keyPrefix, i)
        for _, hash := range bf.hashes(key) {
            if err := bf.redisClient.SetBit(bf.ctx(), bitSetKey, hash, 1).Err(); err != nil {
                return err
            }
        }
    }
    return nil
}
 
// 检查元素是否可能存在于布隆过滤器
func (bf *BloomFilter) Exists(key string) (bool, error) {
    for i := 0; i < bf.bitSetCount; i++ {
        bitSetKey := fmt.Sprintf("%s:%d", bf.keyPrefix, i)
        var allBitsSet bool
        for _, hash := range bf.hashes(key) {
            bit, err := bf.redisClient.GetBit(bf.ctx(), bitSetKey, hash).Result()
            if err != nil || bit == 0 {
                allBitsSet = false
                break
            }
            allBitsSet = true
        }
        if !allBitsSet {
            return false, nil
        }
    }
    return true, nil
}
 
// 哈希函数集合
func (bf *BloomFilter) hashes(key string) []uint64 {
    var hashes []uint64
    for i := 0; i < bf.hashCount; i++ {
        hash := fnv64(key)
        hashes = append(hashes, hash)
    }
    return hashes
}
 
// FNV-1a哈希函数
func fnv64(key string) uint64 {
    hash := uint64(14695981039346656037)
    for i := 0; i < len(key); i++ {
        hash ^= uint64(key[i])
        hash *= uint64(1099511628211)
    }
    return hash
}
 
func (bf *BloomFilter) ctx() *redis.Context {
    return bf.redisClient.Context()
}
 
func main() {
    // 假设已经设置了Redis客户端和其他参数
    redisClient := redis.NewClient(&redis.Options{})
    keyPrefix := "myBloomFilter"
    size := 10
    hashCount := 10
 
    bf := NewBloomFilter(redisClient, keyPrefix, size, hashCount)
    // 添加元素
    bf.Add("someKey")
    // 检查元素是否存在
    exists, err := bf.Exists("someKey")
    if err != nil {
        panic(err)
    }
    fmt.Printf